ALBANY - When the first defensive unit has been called onto the field in each of the first six practices of training camp, Mathias Kiwanuka has trotted out with his teammates. That's nothing new for the defensive end who, when healthy, has been a starter for most of his career with the Giants.

The strange part for Kiwanuka will be when the first unit heads out and he's left there, standing on the sideline.

With Pro Bowler Justin Tuck at one end position and Pro Bowler Osi Umenyiora returning from knee surgery at the other, Kiwanuka's role is changing. Again. It used to be that he'd switch positions. Now he's switching status.

"It's tough," he said of being relegated to a backup. "I'm not going to lie about it. It's not the position that I want to be in. But you just have to roll with the punches and be able to go out there and perform and do your best and know that something good is going to come out of it."

With the Giants cautiously easing Tuck and Umenyiora through these first days of camp, each has been working in only one of the two practices per day. That leaves Kiwanuka to fill in for one or the other.

"There was no doubt in my mind that I was going to get a lot of practice reps coming in here," he said. "Those guys, they have their own issues, and I didn't expect both of them to go in both practices every day."

But he also knows that come September, they will be going every Sunday. Kiwanuka said he's been grappling with coming off the bench for a while.

"There's a moment every day when it sinks in," he said. "I'm a player. I'm here to play. I've been a starter for a long time and that's where I want to be."

He added: "The only thing that bothers me is not having that tag as a starter. It's a pride thing."

Tuck said it's no big deal, comparing the three-man rotation to the one that helped the Giants win the Super Bowl. That year Michael Strahan and Umenyiora were the starting ends and Tuck came in to relieve them.

"He might not be out there on the first play, but in the fourth quarter, in the trenches, Kiwi is going to be out there on the field for us," Tuck said. "If anything, him not being a starter is a technicality."

Still, it was easier for Tuck to handle the rotation than Kiwanuka. Tuck had never been a starter and was just emerging as a dominant player. Kiwanuka has already been a starter and could see the new setup as a demotion.

"If it becomes an issue," Tuck said, "I'll sit down the first play of the game."

Kiwanuka doesn't want it to become an issue, either. He said he's been a captain in high school and college, and has had to talk to players who were in the situation in which he finds himself.

"The thing I've told them is that you have to make them play you," he said. "I have to, at this point, take my own advice."

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